 
 (deftest root-successors-test
   (testing "Number of root node successors."
-    (is (= 2 (-> (lg/to-graph standard-program-1)
+    (is (= 2 (-> (lg/->graph standard-program-1)
                  (g/successors lg/root-node)
                  count)))
-    (is (= 1 (-> (lg/to-graph standard-program-2)
+    (is (= 1 (-> (lg/->graph standard-program-2)
                  (g/successors lg/root-node)
                  count)))
-    (is (= 3 (-> (lg/to-graph standard-program-with-meta)
+    (is (= 3 (-> (lg/->graph standard-program-with-meta)
                  (g/successors lg/root-node)
                  count)))))
 
 (deftest root-successors-names-test
   (testing "Root node successors names."
-    (is (= #{"about" "meta" :entities} (-> (lg/to-graph standard-program-with-meta)
+    (is (= #{"about" "meta" :entities} (-> (lg/->graph standard-program-with-meta)
                                            (g/successors lg/root-node)
                                            set)))))
 
 (deftest entities-successors-test
   (testing "Number of entities-dispatch-node successors."
-    (is (= 3 (-> (lg/to-graph standard-program-1)
+    (is (= 3 (-> (lg/->graph standard-program-1)
                  (g/successors lg/entities-node)
                  count)))
-    (is (= 4 (-> (lg/to-graph standard-program-11)
+    (is (= 4 (-> (lg/->graph standard-program-11)
                  (g/successors lg/entities-node)
                  count)))
-    (is (= 3 (-> (lg/to-graph standard-program-2)
+    (is (= 3 (-> (lg/->graph standard-program-2)
                  (g/successors lg/entities-node)
                  count)))
-    (is (= 0 (-> (lg/to-graph no-entities-edge-case)
+    (is (= 0 (-> (lg/->graph no-entities-edge-case)
                  (g/successors lg/entities-node)
                  count)))
-    (is (= 0 (-> (lg/to-graph no-entities-no-about-edge-case)
+    (is (= 0 (-> (lg/->graph no-entities-no-about-edge-case)
                  (g/successors lg/entities-node)
                  count)))))
 
 (deftest entity-property-test
   (testing "Name of properties of a specific entity."
     (is (= #{"name" "surname" "nickname" "honors"}
-           (let [g (lg/to-graph standard-program-1)
+           (let [g (lg/->graph standard-program-1)
                  n "Musician"]
              (->> (g/successors g n)
                   (mapv #(:name (g/attrs g %)))
                   set))))
     (is (= #{"name" "location"}
-           (let [g (lg/to-graph standard-program-1)
+           (let [g (lg/->graph standard-program-1)
                  n "Festival"]
              (->> (g/successors g n)
                   (mapv #(:name (g/attrs g %)))

          p3 {:name "bands" :type {:coll :ref-to :signature "Band"}
              :gui-label "participant bands"}]
      (is (= 0
             (-> (lg/to-graph standard-program-no-refs)
                 (g/out-edges (lg/build-property-label p0 "Musician"))
                 count)))
      (is (= 0
             (-> (lg/to-graph standard-program-no-refs)
                 (g/out-edges (lg/build-property-label p01 "Musician"))
                 count)))
      ;; whole-part relationship
      (is (= "Category"
             (-> (lg/to-graph standard-program-cardinality-1)
                 (g/out-edges (lg/build-property-label p1 "Category"))
                 first :dest)))
      (is (= "Band"
             (-> (lg/to-graph references-1)
                 (g/out-edges (lg/build-property-label p2 "Musician"))
                 first :dest)))
      (is (= "Band"
             (-> (lg/to-graph references-1)
                 (g/out-edges (lg/build-property-label p3 "Festival"))
                 first :dest))))))

(deftest property-reference-cardinality-test
  (testing "Cardinality of the property-entity relationships."
    (let [g (lg/to-graph references-1)
          p1 {:name "band" :type {:one :ref-to :signature "Band"}
              :gui-label "Of band"}
          p2 {:name "bands" :type {:coll :ref-to :signature "Band"}

(deftest cardinality-graph-presentation-test
  (testing "If cardinality expressed through uni-model is established in graph
 representation of the program."
    (let [g (lg/->graph references-1)
          band-particip {:name "participated" :type {:coll :ref-to :signature
                                                     "Festival"}
                         :gui-label "Participated in"}
